1. Field of the Invention
This invention relates to venographic devices and is directed more particularly to a venogram injector assembly.
Venography relates to the injection of an aqueous radiopaque solution into a peripheral vein of an extremity accompanied by a series of roentgenograms. A venipuncture is performed on one of the distal small tributaries of the hand or foot and the injection of a suitable amount of the radiopaque solution is made by syringe injection. Under fluoroscopic visualization, the movement of the substance through the venous vasculature may be followed. Roentgenograms are made when optimal filling of the various portions of the pertinent venous anatomy are obtained, thereby recording the anatomy and any pathological changes therein.
2. Description of the Prior Art
In the performance of the aforementioned procedure, it is necessary that a radiologist maintain a continuous flow of the radiopaque solution to insure complete venous filling and to minimize dilution of the injected solution by the nonradiopaque blood which continues to flow within the veins. The amount of substance required usually necessitates the use of a plurality of syringes. During an exchange of syringes, the radiopacity of the solution becomes attenuated as it is displaced by the influx of blood. Further, in the haste to exchange syringes, an air bubble is sometimes introduced and can simulate venous thrombosis if it lodges within one of the veins under scrutiny.
Simultaneously with the injection and exchange of syringes, the radiologist must control a fluoroscopy unit and make the appropriate exposures. Thus, the radiologist has in the past generally had one hand occupied with a syringe in an attempt to maintain a continuous injection and the other hand occupied with the fluoroscope in order to study and film the venous anatomy.